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A certain number of samples were exposed an in-situ heat treatment after the deformation while other samples were immediately quenched after the forging to preserve the deformed microstructure, which was measured by optical microscopy and electron microscopy.
From these grain boundary precipitates, laths of an identical orientation grow into the parent ferrite grain revealing a micro structure similar to Widmannstätten ferrite [2].
In this image the austenite is located at the ferrite grain boundaries.
The diagrams depict the increase in grain size of both phases with increasing deformation temperature.
Figure 9, Statistical distributions of the grain size (a-c) and the average misorientation angle ω of a grain (d-f) for samples deformed at temperatures of 950°C (a and d), 1050°C (b and e) and 1200°C (c and f).

The rolling does not influence the average size of the grains which is, in every direction, 22 µm for the ferrite grains and 16 µm for the pearlite grains.
The distance between two pearlite bands corresponds to one or two ferrite grains.
It is equivalent to the size of 1 ferrite and 2 pearlite grains and corresponds to the case when the crack exceeds the main microstructural barrier (Fig. 3.a) [11].
The number of cycles of initiation was identified by means of the replica technique.
It has a ferrite grain size length.

These dilatometric studies are confirmed and extended with the study of the austenitic grain from the austenitizing temperature dependence, Fig. 2.
Impact of austenitizing temperature and duration of exposure on the size of the austenite grain steels: a - 70H3G2VTB b - 70H3G2FTR; c - 100H3G2MTR.
In the investigated steels at temperatures of 900 –1000 °C austenitizing there is no intensive growth of austenite grains, in the structure grains of of 5 – 8 microns size can be observed.
Raising the temperature causes dissolution Me7C3 type carbides that facilitates further growth of austenite grains.
Increasing the tempering temperatures up 700 ºC leads to the increase of softening intensity, which is associated with rapid coagulation carbide phases, accompanied by a decrease in the number of particles.

It was found that the concentration of lanthanum increases the average crystalline grain size decreases.
It can be noted that lanthanum concentration has significant influence on BT grain growth.
As the concentration of lanthanum increases the average grain size decreases.
A model structure used for the diffraction pattern fitting exhibited a P4mm space group (SG number: 99) (Fig.2) [8].
It can be noted that lanthanum concentration has significant influence on BT grain growth.

The microstructure consists of martensite, which is formed inside the borders of the former austenite grain, retained austenite, which is presented in small amounts in the form of separate islands, and thin layers of δ-ferrite, which is located on the borders of the former grain austenite.
The size of the former austenite grain conforms to scales ranges №6 - 7 (figure 1a, b, table 2).
It is shown that the microstructure of sample number 7-10 present medium-needled (rating № 5) and big-needled (rating №7) martensite with needle size 8-13 microns.
The amount of primary austenite grains corresponds №6 (figure 1b, table 2).
Surfaced layers’ chemical composition, hydrogen contain, wear and hardness Sample number Components weight content % [H], cm3/ 100g Sampals hardness, HRC Samples wear, grams per revolution.

Furthermore, the powder size shows an inhomogeneous distribution, and most of them (small powders) are smaller than 10 μm, only small number of them (large powders) is larger than 10 μm (Figs. 2 and 3).
The white eutectic phase solidified in the final stage of solidification is left in the grain boundaries within the powder.
It can be found that the grains within the powders grow through merged (comparing Fig. 1b and Fig. 4a), and the powders coarsen (Fig. 4b), due to the solution of eutectic phase.
Furthermore, the rapid rise temperature during the early stage (Fig. 5) made the eutectic phase have no enough time to completely dissolve into grains when the temperature reaches the eutectic point.
So the phenomenon occurring in the early period of 0-5 min is the rapid coarsening of grains and powders.

Natural silicate rocks, which have high physicochemical characteristics are used as fillers of various grain sizes.
The grain size composition 1of asphalt concrete mixture is shown in Fig. 2, the component composition is shown in Table 1.
Similar studies were carried out for a fine-grained mixture G2.
Grain size of mineral material, mm Fig. 3.
Grain composition of fine asphalt concrete mix Table 3.

The grain size of ZnO:Ag films were found in the range 76.5 to 304.8 nm.
The low roughness resulted from uniform small grains distributed on film surface.
Reduced grain size leads to less rough surface [10].
The grain size increases up to 304.8 nm by 4%Ag doping.
This is proven by the decline in the number of E.coli bacteria after being treated with ZnO:Ag, compared to ZnO.

From Fig.2(d), NKBT20/STO thin film is of the largest grain size, the most clear grain boundary and the smallest pinholes and voids among these thin films, which may be beneficial to enhance its ferroelectric and dielectric properties due to the easiness of the reorientation of domains [11].
On the other hand, the improvement of crystallinity lessens the grain boundary effect on resistance and leads to a small leakage current density [13].
The reduced volume fraction of the grain boundary and the domain wall make the reorientation of the domains easier.
With the increase of grain size, the number of domain switching variants will increase to enhance the ferroelectric properties [11].
From Fig. 2, the NKBT20/STO thin film has the largest grain size, which contributes to the enhancement of 2Pr value.

The measurement number corresponds to a specific location of the test at the diameter of the rod (4 - around the axis 1, 7 - near the surface).
Macrostructure of the rod casted using the modifier was characterized by fine, equiaxed grains.
In the case of ingot without grain refiner, a different angle of columnar grains was observed.
In the case of casting process with grain refiner equiaxed grains were observed (refinement of structure).
The addition of grain refiner causes a reduction of segregation effect.